lib/libelf/libelf_allocate.c

   1 /*-
   2  * Copyright (c) 2006,2008,2010 Joseph Koshy
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  */
  26
  27 /*
  28  * Internal APIs
  29  */
  30
  31 #include <sys/cdefs.h>
  32
  33 #include <sys/errno.h>
  34
  35 #include <assert.h>
  36 #include <errno.h>
  37 #include <libelf.h>
  38 #include <stdlib.h>
  39 #include <string.h>
  40
  41 #include "_libelf.h"
  42
  43 LIBELF_VCSID("$Id$");
  44
  45 Elf *
  46 _libelf_allocate_elf(void)
  47 {
  48         Elf *e;
  49
  50         if ((e = malloc(sizeof(*e))) == NULL) {
  51                 LIBELF_SET_ERROR(RESOURCE, errno);
  52                 return NULL;
  53         }
  54
  55         e->e_activations = 1;
  56         e->e_hdr.e_rawhdr = NULL;
  57         e->e_byteorder   = ELFDATANONE;
  58         e->e_class       = ELFCLASSNONE;
  59         e->e_cmd         = ELF_C_NULL;
  60         e->e_fd          = -1;
  61         e->e_flags       = 0;
  62         e->e_kind        = ELF_K_NONE;
  63         e->e_parent      = NULL;
  64         e->e_rawfile     = NULL;
  65         e->e_rawsize     = 0;
  66         e->e_version     = LIBELF_PRIVATE(version);
  67
  68         (void) memset(&e->e_u, 0, sizeof(e->e_u));
  69
  70         return (e);
  71 }
  72
  73 void
  74 _libelf_init_elf(Elf *e, Elf_Kind kind)
  75 {
  76         assert(e != NULL);
  77         assert(e->e_kind == ELF_K_NONE);
  78
  79         e->e_kind = kind;
  80
  81         switch (kind) {
  82         case ELF_K_ELF:
  83                 STAILQ_INIT(&e->e_u.e_elf.e_scn);
  84                 break;
  85         default:
  86                 break;
  87         }
  88 }
  89
  90 #define FREE(P)         do {                            \
  91                 if (P)                                  \
  92                         free(P);                        \
  93         } while (0)
  94
  95
  96 Elf *
  97 _libelf_release_elf(Elf *e)
  98 {
  99         Elf_Arhdr *arh;
 100
 101         switch (e->e_kind) {
 102         case ELF_K_AR:
 103                 FREE(e->e_u.e_ar.e_symtab);
 104                 break;
 105
 106         case ELF_K_ELF:
 107                 switch (e->e_class) {
 108                 case ELFCLASS32:
 109                         FREE(e->e_u.e_elf.e_ehdr.e_ehdr32);
 110                         FREE(e->e_u.e_elf.e_phdr.e_phdr32);
 111                         break;
 112                 case ELFCLASS64:
 113                         FREE(e->e_u.e_elf.e_ehdr.e_ehdr64);
 114                         FREE(e->e_u.e_elf.e_phdr.e_phdr64);
 115                         break;
 116                 }
 117
 118                 assert(STAILQ_EMPTY(&e->e_u.e_elf.e_scn));
 119
 120                 if (e->e_flags & LIBELF_F_AR_HEADER) {
 121                         arh = e->e_hdr.e_arhdr;
 122                         FREE(arh->ar_name);
 123                         FREE(arh->ar_rawname);
 124                         free(arh);
 125                 }
 126
 127                 break;
 128
 129         default:
 130                 break;
 131         }
 132
 133         free(e);
 134
 135         return (NULL);
 136 }
 137
 138 Elf_Data *
 139 _libelf_allocate_data(Elf_Scn *s)
 140 {
 141         Elf_Data *d;
 142
 143         if ((d = calloc((size_t) 1, sizeof(Elf_Data))) == NULL) {
 144                 LIBELF_SET_ERROR(RESOURCE, 0);
 145                 return (NULL);
 146         }
 147
 148         d->d_scn = s;
 149
 150         return (d);
 151 }
 152
 153 Elf_Data *
 154 _libelf_release_data(Elf_Data *d)
 155 {
 156
 157         if (d->d_flags & LIBELF_F_DATA_MALLOCED)
 158                 free(d->d_buf);
 159
 160         free(d);
 161
 162         return (NULL);
 163 }
 164
 165 Elf_Scn *
 166 _libelf_allocate_scn(Elf *e, size_t ndx)
 167 {
 168         Elf_Scn *s;
 169
 170         if ((s = calloc((size_t) 1, sizeof(Elf_Scn))) == NULL) {
 171                 LIBELF_SET_ERROR(RESOURCE, errno);
 172                 return (NULL);
 173         }
 174
 175         s->s_elf = e;
 176         s->s_ndx = ndx;
 177
 178         STAILQ_INIT(&s->s_data);
 179         STAILQ_INIT(&s->s_rawdata);
 180
 181         STAILQ_INSERT_TAIL(&e->e_u.e_elf.e_scn, s, s_next);
 182
 183         return (s);
 184 }
 185
 186 Elf_Scn *
 187 _libelf_release_scn(Elf_Scn *s)
 188 {
 189         Elf *e;
 190         Elf_Data *d, *td;
 191
 192         assert(s != NULL);
 193
 194         STAILQ_FOREACH_SAFE(d, &s->s_data, d_next, td) {
 195                 STAILQ_REMOVE(&s->s_data, d, _Elf_Data, d_next);
 196                 d = _libelf_release_data(d);
 197         }
 198
 199         STAILQ_FOREACH_SAFE(d, &s->s_rawdata, d_next, td) {
 200                 assert((d->d_flags & LIBELF_F_DATA_MALLOCED) == 0);
 201                 STAILQ_REMOVE(&s->s_rawdata, d, _Elf_Data, d_next);
 202                 d = _libelf_release_data(d);
 203         }
 204
 205         e = s->s_elf;
 206
 207         assert(e != NULL);
 208
 209         STAILQ_REMOVE(&e->e_u.e_elf.e_scn, s, _Elf_Scn, s_next);
 210
 211         free(s);
 212
 213         return (NULL);
 214 }